Coming back to the second “world”…

[Four updates added on September 24, 2013.]

0. Coming back to the second “world,” I would like to briefly note a few points concerning it. … But before coming to these points, first, in case you have joined late and so don’t know what I mean by the term “second ‘world’,” let me tell you that in brief.

1. The term “second ‘world'” means: a view of the physical world which would correspond, roughly speaking, with the Newtonian physics. In particular, it refers to a broad, objective view of the physical world as is implied by, or is implicit in, the state of physics as it existed after Galileo and Newton, but before the discovery of the laws of electromagnetism. Roughly speaking, the mid-17th century to, say, the early 19th century.

This “world” consists of uncharged bodies not only colliding with each other but also sucking up the gravity field-fluid. The first “world,” in contrast, would be this second world, minus the phenomenon of gravity. I had written about these ideas in my recent post here [^].

The first world really speaking doesn’t pose much of a conceptual problem to any one, because it is a local theory, and a relatively simpler one at that. The only kind of entities making it up are all definite objects—either discrete objects like apples and planets, or such continua that their defining properties always are defined in reference to a definite portion of that continuum, as in the classical fluid and solid mechanics. Further, all entities in this world are material (i.e. mass-possessing) ones. And, all the interactions are via a common surface between the directly touching bodies.

The second world, as I indicated in my earlier post, posed conceptual problems back then (and it continues to stump people even today—if they at all care to think about it) because gravity adds two difficult features: (i) forces acting through a “void,” and (ii) instantaneous action at a distance (IAD).

I had then sketched a possible solution involving a hypothetical, massless, gravity field-fluid.

In the follow-up post [^], I had referred you to Wang’s papers, and had asked if scientific papers like these would be enough. And, also what additional input would be necessary for you to be convinced that a hypothetical massless fluid indeed makes for a first-class object of physics.

2. The main paradox:

For convenience, let me now more or less fully reproduce, paraphrasing only a bit here and there, what I said by way of the question, right in that first post about the conceptual trouble with that kind of a “fluid.”

The first issue that arises in the second world, viz., forces being transmitted through a void, is a more serious challenge, because it spoils the neat view otherwise built for our first world—a view of localized, definite objects exchanging momenta/energy through direct contact via a common surface (collisions or fluxes).

So, now, a question arises: Where do we place the field of gravity? Is gravity an attribute of the distinct material objects (such as apples or planets), or is it an attribute of the “void” in between them.

The issue is not as simple as it might sound to you.

If you say that gravity is an attribute of the void, then an immediate next question is: does gravity exist in a world devoid of the material objects like apples and planets? If so, what does the field do? Forcing nothing is a contradiction in terms—the definition of force involves the change of momentum of a material object like an apple or a planet.

There cannot be a force in a field if there is nothing to force from/to. Assuming unit masses for all entities, mathematically, “forcing” is nothing but another name for “accelerating.” Even if you hypothesize the existence of a definite, lawful, but massless physical object for the Newtonian gravitational field, i.e. one with identity, a question still remains: how do you define forces (i.e. accelerations) within this object? A massless forcing object can make sense but only when there is some mass to be accelerated.

Naturally, you have to attribute the phenomenon of gravity to the usual material objects: the stars and planets, for example. If so, you have come back to square one: you can no longer explain interactions via simple direct contacts between material bodies. If gravity is to be attributed to the material bodies themselves, then no mechanism is left to explain how it can act over the “void” (or “free space” or whatever).

This theoretical complication is what Newton himself should have commented upon. But, he didn’t. His shortcoming.

3. The (other) candidate solutions:

My further ‘net searches threw quite a few fascinating ideas. I will note down just a few of them (i.e. apart from Wang’s papers that I have noted earlier in this series).

First, the obligatory Wiki articles, and the references therein: Aether the Classical Element [^], Aether Theories [^], Mechanical Explanations of Gravitation [^], and, though meant for electromagnetism, if you wish to use similar ideas also for gravity, Luminiferous Aether [^]. …

BTW, the coverage of the aether-related ideas on the Internet in general, and on Wiki in particular, has improved a significantly great deal since the time not so long so—around 2004/05 times, when I was doing my PhD. At that time, most pages were amateur or even worse—crackpot! The only exceptions were a few groups like a nonlinear studies center in an Austrian university, or so. [Update on September 24, 2013: Link, here[^]]. BTW, my PhD papers had assumed an aether hypothesis, but quite different from what people meant about it. Which brings us to the next set of material.

  • The “MountainMan” collection of links [^]. Very comprehensive. (They didn’t miss Dirac’s surprisingly pro-aether viewpoint either!)
  • The “Cellular Universe” Web site, with an excellent summary of the views of the aether idea, throughout history (right in the format of a table/timeline!) [^]. You may want to spend some time exploring some related material (like that on cosmology) on this site; consult the links given in the side bar of that site.
  • There were quite a few others too, though the links already given would cover pretty much the entire territory one way or the other. … For instance, see this blog post [^]. Its presentation is good, but all those points are one or the other already covered in the links (and the sub-links) given above.

Comment: Realize that none of these solutions, IMO, fully satisfactorily resolve the main paradox which I have noted above.

For many of these aether theories, if you wish to use a simple heuristic to expedite your reading (though I wouldn’t advise you to outright dismiss any idea out of hand), just ask yourself this simple question:

If it is a continuum aether, is it massive or massless? If the former, how does the theory account for Newton’s three laws for the massive objects? Are they modified too? Must they? And, if the latter, then what specific characteristics of aether are proposed here that would go on to provide a mechanism for the gravity force?

For certain other, particles-based theories (i.e. particles of aether), always ask yourself: Is this theory philosophically satisfactory? What exists in between those aether particles? void?

Have fun.

4. “But why should I pursue it in the first place? What is the fallout?”

You may now wonder, of course, where the fun is, in all this “back-dated” enterprise.

You may perhaps say something like: “All we seem to be doing here is to dig through the errors of the other people, and, that too, of those who are long dead. There is no fun in going through the wrong theories of the ancient people [like Newton and all!], how they thought. Einstein proved them all wrong, and the 20th century—including all the finest and costliest experiments performed till date—has proved Einsten right.” And, continuing, you may then ask me: “How is your paradox relevant to solving the really important problems (or even paradoxes) facing today’s physics? Why dig up old paradoxes when new ones are available, and old ones are already resolved?”

I won’t argue a lot here. By way of my answer, I will only note down a couple of points. [Many other smart people, I am sure, would have already noted these by now, without me having to tell them about that…. But still…].

(i) The second world is important because it is the simplest toy world that still carries an important, defining feature of the standard model of the modern particle physics: viz., the division of all things (they call it “particles”) into two mutually exclusive and collectively exhaustive classes: the massive particles (i.e. the fermions) and the massless particles (i.e. the bosons). If you know how to (properly) quantize a continuum (the way I have done in my published papers and also writings on the blogs etc.), then, in solving the toy problem of the gravity-fluid, you create a platform that would be very directly useful in solving some of the really difficult conceptual riddles concerning the modern standard model. … I won’t name them. You should know what those are. [LOL! Why? Because you were concerned with the modern standard model, that’s why!]

(ii) If you can resolve the main paradox, by giving a logically consistent and complete (i.e. fully satisfactory) aether-based description even if only for the second world, then, that accomplishment, by itself, would mean that you had overcome the greatest hurdle in resolving the most difficult paradoxes related to the relativity theory as well. They would go out the door in one go. Web pages like, e.g., this excellent set [^], would be taken down, though the Web sites themselves (including that Web site) will still continue to thrive—by focusing on other, better, more authentic problems of physics. Why?

Because, this way, you would be able to give an “engineer’s” description for the physical world, a description that, at its most fundamental level, requires only a 3D Euclidean geometry for space, and a basically separate scalar for time. (Time would no longer be a “dimension” in the theory; it would be just a parameter, really speaking.)

Imagine what kind of a simplification in the conceptual structure of physics that would represent.

… And, yes, if you wished, you would still be free to play with the “spacetime” continuum, manifolds, their contortions… all those concepts as well, though you wouldn’t have to use them. You may find reasons (perhaps even good reasons) to continue using them for mathematical convenience in (some, not all) applications, that’s all. [For instance, you may find some convenience in error analysis of some numerical analysis code, or in presenting a more concise deductive formulation.] But not in the basic physics theory.

[Update on September 24, 2013:

This update on September 24, 2013, over.]

Of course, your intermediate step would still consist of first resolving a similar riddle for the third world (that of EM) as well. Yet, the nature of the issues is such that if you can resolve the paradox even if only in the second world, then that by itself would be a great step forward. You see, the paradox concerning the third world (i.e. the one concerning the EM field) is only mathematically a bit more complicated—conceptually, not so much, though some conceptual advancements would still be necessary, too (other than what I have already explicitly noted or hinted at).

3. One more reason why you can give it try. It’s because… the paradox—at least that in the second world—most certainly is resolvable.

And, how do I know that?

…[Suppresses laughter] …

Time to run through the description of the main paradox, again? See the main point 2. above. (… It could be put in a better, more precise way, but what I have already noted down seems to be enough. At least to me, and at least for a blog-post, and at least for the time being. It puts the issue directly enough. … So, there!)

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Updates on September 24, 2013:

Update 1. Why the classical fluid mechanics belongs to the first world:

In the classical fluid mechanics, there also is a flux of mass (in addition to that of momentum) which, at the first sight, seems unlike the first world, because with the solid colliding balls of the first world, there is a transfer of only momentum, not of mass.

However, we can still regard the classical fluid as belonging to the first world, because mass of the fluid is a property defined for both the parts of the material continuum sharing their common surface, and both these defining parts are definite material objects.

The classical fluid is nothing but just a limiting case, obtained by applying a mathematical homogenization (or “squishing” i.e. “continuum-ization”) procedure to a collection of what otherwise are only discrete material objects occupying a defining volume in the first world. For instance, a grosser-scale volume of air is taken as the classical fluid material, even though the reference volume itself is made up of a large number of tiny, discrete, gas “molecules” which themselves can be taken as the usual solid objects of the first world; ditto, for water and other liquids.

Left as an exercise for you: Figure out why also friction (e.g. Newton’s law of friction) does not pose any deep conceptual issue in the first world.

Update 2: A link to the Austrian university which was doing research on aether-based descriptions in the mid-naughties, has been inserted inline; it was the AINS [^]. BTW, I had made a reference to Prof. Gr\”{o}ssing’s papers, in one of my PhD research papers, too.

Update 3:  The additional beneficial fallouts of a new conceptual perspective:

Another point. I wish to note a bit more on the beneficial fallouts of a new conceptual perspective such as the resolution of the main paradox concerning the second world, as noted in these blog posts.

Though the final quantitative predictions of both the mainstream theory of Newtonian gravitation and an aether-based theory may outwardly seem to remain quantitatively the same, it still is not proper to dismiss the aether-viewpoint.

A plain epistemological fact is that with a new (objectively valid) conceptual viewpoint, new progress into the as-yet-not-even-imagined territory also becomes at all possible.

The progress of physics does not always depend only on new experimental observations; crucial to the inductive process of discovery also is the advancement in the conceptual perspective. (Claiming otherwise is a direct case of MBD—the mind-body dichotomy.)

Remember, consciousness is finite, not infinite. In other words, we have limitations to how much of a further progress we can make, given an already existing level of knowledge, and, given a particular conceptual vantage point that goes with it (at least implicitly).

Due to the finitude of our consciousness, given a particular conceptual viewpoint (implicit in a particular state of knowledge), some as-yet unknown facts, even if logically not inconsistent with that older viewpoint, still become so conceptually distant as to fall out of the limited range of any possible mental grasp, and hence, out of the range of any possible application involving them—or even the more basic discoveries of those facts.

For instance, Newton’s original formulation of the laws of dynamics, which is essentially a formulation in terms of vector mechanics (though the concept of a vector had not yet been explicitly grasped in his time) does remain applicable, in principle, to every dynamical problem of the first world. Yet, a very large range of problems become tractable only via the variational/energy-based approaches (or the Lagrangian/Hamilton reformulations). [BTW, Newton was also the first person to correctly pose and solve a variational problem.] In the classical physics, the law of conservation of energy does not add anything new to the already known dynamics at its most fundamental level.  [Incidentally, I still remember how discovery of this fact had come as a shock to me!] But try to use the original Newtonian mechanics in calculations of, say, the heat of a chemical reaction!

And, my point here is deeper than that. Among two or more conceptual viewpoints explaining the same set of facts, the most fundamental among them is the most crucial—abandoning it affects the scope of any new possible discoveries the worst. Physical observation is basic to mathematics—and not vice versa. Hence, abandoning a more fundamental physics viewpoint affects the new discoveries the worst.

Thus, not only inventions of new mathematical principles, but also new physical discoveries themselves become at all possible only when you actively adopt a new conceptual perspective—even if its initial scope seemingly refers to the same old set of facts.

As an example of this latter fact right in our present context, see the ease with which Wang’s paper suggests the possibility that the exponent “2” in the inverse-square law may not be a constant—and the ease with which you can understand it, too! Otherwise, precisely due to the much-prized mathematical “tightness” of the Poisson-Laplace equation—and, if you want, you can also throw in here any supposed beauty of the harmonic analysis, the beauty of its symmetry, et cetera—the very idea of a variable exponent in a law verified in as many separate instances as Newton’s Law of Universal Gravitation, would look wacky and crackpot to any one—especially if the paper were not written using LaTeX! …

When Dirac in fact made a similar suggestion concerning the possible variability of the universal “constants” of physics, he was rightly held in high regard and admiration for that idea. Understandably so. Abandoning aether, it would take a genius to think of varying just that part of, say, the “spacetime” (i.e. without using even the hyphenation mark [whether using LaTeX or not]). Since most physicists by then had abandoned that idea of the aether, the suggestion did look awesome to many of them. From their viewpoint, it would take not just a normal genius but, say a genius^genius, to conceive of so “bold” and such “daring” an idea.

Well, there is some boldness and daring in here, but it’s not in the detail of suggesting the possible variability of what we take as universal constants—I mean to say, it’s not an issue limited to making a variable out of a constant; it does not concern an apparently marvellous piece of a mathematical thought. Instead, the boldness and daring is in trying to keep a more fundamental physics hypothesis, that of aether, in the physics theory, despite its denials by the authorities of the day. Once you put aether back into the physics theory (or never fully abandon it as probably was the case with Dirac—at least privately to his own mind), it then looks a plain and relatively simpler consequence of that theory.

Now, you can always put such a consequence in precise mathematical terms, which, taken out of context, is guaranteed to look unbelievably awesome. [Morally lesser professors at the world’s leading universities have always employed this trick.] Further, once the concrete suggestion comes out, you can always go back into the woodwork (or near your blackboard), deduce—in part using the new suggestion—and then, come out of the woodwork and say that it was already deducible even from the plain old mathematics, and use that claim both to make the new advancement look lesser, and to continue justifying your dogma. [Morally lesser professors at the world’s leading universities are known to employ also this trick.]

…And, this variability of the supposed universal constants was just an example. .

.. New conceptual perspectives, even if based on the same set of observational referents, enable new discoveries that would otherwise remain out of the reach of the human mind that uses only an existing conceptual framework which contains some unresolved “merely philosophical” paradoxes. Every fundamentally new field of mathematics—i.e., if it is authentically new (and not just a deductive avatar of an existing one) has, in fact, depended precisely on such conceptual advancements coming from physics (or the “physical” thinking).

The Objectivist epistemology even has terms for such things: the DC [not that one!], the CCD [and now you believe me, don’t you?], the rule of fundamentality, and all that. … OK. More, later.

Update 4: Added the usual section about a song I like.

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A Song I Like:

(Marathi) “hari bhajanaaviN kaaL ghaalavu nako re…”
Singer [of the version I like]: Dashrath Pujari
Music [of the version I like]: Dashrath Pujari (?)
Lyrics: Sant Sohirobaanaath

[PS: Just a stray thought…. Should I have put these updates in a separate post? … May be I will… I will think about that later on… For the time being, enough is enough!]



7 thoughts on “Coming back to the second “world”…

  1. i have been following your blog for quite a while now… knowing you this long (courtesy: your webpage) i feel you will most probably not reply to my previous question! nevertheless i am very curious to know what you feel about ‘this’ universe being electric in nature… a simple “it is all crap” or something more “tangy?!” would do! 🙂

  2. Pingback: The “electric universe” belongs to the third+ world… | Ajit Jadhav's Weblog

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